The JavaCore plugin was designed to act as a central location for the management of classpaths and sourcepaths that may be used by other Java-centric plugins. It is obsolete and its functionality exists in ProjectViewer and JavaSideKick.

The JBrowse plugin allows for easy navigation of Java source code by providing a highly customizable tree-view of a file's classes, fields, and methods.
This version is available for dependency purposes only.
It is recommended you use JavaSideKick 2.0 instead.
It is also recommended that plugin authors who have this listed as a dependency remove it from the dependency list (in favor of JavaSideKick) so we can remove it from plugin central.